1. Field of the Invention
The invention generally relates to a treatment apparatus for providing treatment to a food product by impingement. In one aspect, the invention relates to a treatment apparatus having a plurality of chambers, one of the chambers defining a treatment zone having an ambient pressure and permitting impingement of a treatment fluid upon a food product such that the food product is treated at the ambient pressure. In another aspect, the invention relates to a treatment apparatus having a plurality of chambers, one of the chambers defining a treatment zone having an ambient pressure and permitting impingement of a treatment fluid upon a food product, in a continuous supply of food product, such that the food product is treated at the ambient pressure.
2. Description of the Related Art
The preservation of perishable products has been, and continues to be, the focus of considerable commercial interest. By extending the shelf life of a food product, economic value can be added to that food product. Approaches to this end are many and varied (e.g., tight control of storage conditions, packaging, post and in situ applications of preservatives) and various combinations of these and other techniques are known and in practice to one extent or another.
In the context of one particular group of food products, namely baked goods (e.g., muffins, crumpets, scones, bagels, cookies, breads, etc.), all of the above techniques are in use. For example, baked goods can be placed in frozen or refrigerated storage, covered with anaerobic packaging, and/or supplemented by the addition of preservatives. When such preservatives are used, the preservative can be added to either a batter or a mix from which the baked goods are prepared. Also, the preservative can be applied to finished baked goods. With respect to the finished baked goods, application of a small amount of the preservative can extend the shelf life of the baked goods from a typical 6–8 days to an extended 14–16 days when all other conditions (e.g., packaging, storage conditions, and the like) are equal. These preservatives can include a wide variety of substances (i.e., microbiocidal substances, antimicrobial substances, etc.) such as acetic acid, lactic acid, carbonic acid, mixtures thereof, and the like.
In a typical preservative application process, a conventional treatment apparatus can be employed to administer the preservative. The conventional treatment apparatus essentially contains a movable hood in combination with a base. When in a closed relationship with one another, the hood and the base define a volume. The hood can be manipulated (e.g., raised and lowered) such that the baked goods to be treated can be inserted and removed from the volume. Further, the hood can be equipped with an entry port for receiving a treatment fluid (e.g., a preservative or a mixture containing the preservative such as a vaporized mixture of carbon dioxide and acetic acid). The base can comprise a platen, or in some cases, a platen associated with a movable base conveyor that rides upon the platen.
When the conventional treatment apparatus is in operation, the hood is raised, the baked goods riding on the base conveyor in batches are transported beneath the hood, and the base conveyor is temporarily halted. The hood is then closed over, and sealed against, the platen and/or base conveyor such that a negative pressure (e.g., a vacuum) can be drawn within the volume of the treatment apparatus. After the vacuum is drawn by evacuating atmosphere (e.g., air) from within the sealed apparatus, the treatment fluid can be fed into the treatment apparatus to coat onto and/or penetrate into the external surfaces of the baked goods. The vacuum can promote and/or accelerate absorption of the treatment fluid into the baked goods.
After the baked goods have been treated, excess treatment fluid can be exhausted, the hood of the treatment apparatus can be raised, and the batch of treated baked goods can be removed using the base conveyor. This “treatment cycle”, or application of treatment fluid on a batch-by-batch basis, is normally repeated for each succeeding or successive batch and can take approximately twenty-five to thirty (25 to 30) seconds to complete.
Unfortunately, using the conventional treatment apparatus to treat baked goods on a batch-by-batch basis within a vacuum, as described above, can present a significant number of disadvantages. First, since the conventional treatment apparatus requires production of a vacuum during the treatment cycle, vacuum pumps (or other devices for drawing a vacuum) must be associated with the apparatus. These vacuum pumps can be of significant size, can consume vast amounts of energy, can require elaborate and intricate control systems, and can occupy valuable floor space. Each of these factors can add significantly to the cost of treating food products such as baked products. Thus, potential customers and users can be hesitant to purchase or employ such a treatment apparatus for economic and financial reasons.
Also, since baked goods are typically delivered to a treatment apparatus in an indexed array, further difficulties can arise. An indexed array is produced from a continuous supply of baked goods and is normally used and maintained throughout a significant portion of the baked good preparation process. However, the indexed arrays of baked goods are not compatible with the batch-by-batch treatment offered by the conventional treatment apparatus. Therefore, just prior to encountering the treatment apparatus, the baked goods must be assembled into the batches. Only then can the conventional treatment apparatus treat the baked goods as described above. After treatment, the indexed arrays are usually restored to promote further processing, such as packaging. Thus, the batches are disassembled, the baked goods are collated, and then indexed arrays are reformed. Converting arrays to batches, and batches to arrays, can add time delays in the treatment process. Likewise, conversion can require expensive additional equipment. This additional equipment can occupy valuable floor space, present elaborate controls, require an equipment technician or operator, consume large amounts of energy, and the like. Both the time delays and necessary additional equipment can add to the cost of the baked good treatment process.
Additionally, when the conventional treatment apparatus is imbedded within a typical treatment fluid generation system, a buffer tank is required. Buffer tanks typically comprise either heated or vacuum jacketed devices that are capable of receiving, storing, and expelling treatment fluid. Because the batch-by-batch basis of treatment is used with the conventional treatment apparatus, the fluid generation system will produce the treatment fluid faster than the treatment apparatus can apply the treatment fluid. Thus, the buffer tank is employed to accommodate the excess treatment fluid by acting as a reservoir. The buffer tank permits continuous receipt, and periodic discharge, of the treatment fluid.
Unfortunately, buffer tanks are generally at least ten times the volume of the treatment apparatus to inhibit pressure changes during the application of the treatment fluid. Also, buffer tanks can require multiple modulating control valves, pressure regulators, and a control system. Therefore, buffer tanks can cause time delays and additional costs into the typical fluid generation system using a conventional treatment apparatus.
Thus, an apparatus and method for providing treatment to a food product at an ambient pressure would be highly desirable since such an apparatus and method would eliminate the need for a vacuum pump. Likewise, an apparatus and method for providing treatment to a continuous supply of food product would be highly desirable since such an apparatus and method would eliminate the need for a buffer tank as well as batch assembly and disassembly equipment.